Field of the Disclosure
The invention relates generally to jack stands for vehicles and specifically to universal jack stands that can be used with a variety of vehicle jacks and jack stands that support a vehicle at a common jacking location with the jack.
Related Technology
Elevating a portion of a vehicle typically involves using some sort of jack. For example, many automobiles carry a scissor-type jack to elevate a portion of the automobile in order to change a tire. The jack is placed under a portion of the frame of the automobile and the jack is slowly raised until a platform on the jack engages the frame of the automobile. Thereafter, a user uses the principle of leverage to elevate a portion of the frame. Often, more than one location on the frame needs to be elevated so that a user can repair a portion of the automobile that is only accessible from the bottom. Because most standard jacks are movable, so that the jack may be easily moved to many different portions of the frame, a vehicle supported solely by the jack may be unstable and unsafe to work under. For this reason, a user may place a jack stand under the frame and lower the jack so that the vehicle is supported on the jack stand instead of the jack itself. The jack stand is typically a stable platform for supporting the vehicle. Because the jack and jack stand have individual and separate support structures, the jack stand and jack typically cannot support the vehicle at same location on the frame. This can cause a problem when a manufacturer designates only certain locations as jacking locations. Generally, vehicle manufacturers reinforce certain locations on the frame of a vehicle so that those certain locations can support a portion of the weight of the vehicle when the vehicle is elevated with a jack (hereinafter these locations on the vehicle frame are referred to as “jacking locations”).
Generally, jack stands are pyramid-shaped structures having three or four sides and an adjustable support platform disposed in the top of the jack stand. For example, U.S. Pat. No. 7,207,548 discloses a more or less typical jack stand including four sides that form the shape of a pyramid, a telescoping support member extending from a top portion of the pyramid and a curved horizontal support, often having a U-shape, at the top of the telescoping support member to cradle a portion of the vehicle frame. The support member is often adjustable with a ratchet type mechanism. Problems occur with placement of this type of platform as only certain parts of the frame or undercarriage can fit in the curved horizontal support. While a jack stand is usually more stable than a jack, the jack stand cannot support the vehicle at the same point that is occupied by the jack. As a result, the jack stand often must be placed a considerable distance away from the jacking location in order to find a portion of the frame or undercarriage that is compatible with the top of the support platform, necessarily requiring a higher jacking elevation to accommodate the jack stand location.
In order to solve this problem, systems have been designed to elevate the vehicle with the jack stand itself. For example, U.S. Patent Publication No. 2008/00999745 discloses a three stage jack stand. A lift collar on the top of the jack stand is elevated by a specially designed unique power unit. The power unit includes a pair of lift arms that engage a lower portion of the lift collar on the jack stand. When the jack stand is placed under a vehicle, the lift arms on the power unit move upward to engage a bottom of the lift collar on the jack stand. The lift collar fully supports and elevates the vehicle at all times during the jacking process. One drawback to this type of arrangement is that the jack stand and the power unit are specially designed for one another. Thus, this type of jack stand and power unit are not compatible with contemporary vehicle jacks, such as scissor jacks, floor jacks or racing jacks. Moreover, this type of power unit is not compatible with typical jack stands and/or may be too tall to fit under some vehicles.